I'm not sure why anyone would have an issue with any of this. There were situations during World War II where African Americans were completely separated from the eastern front, German society or Allied High Command. Not only would such stories minus African Americans would make great movies in the future but they already have been made as great movies in the past. That's your point. It's a great point. And many moviegoers of every shade or creed would enjoy such movies. I know I would. And have.
However, World War II was a global conflict involving many different people, millions in fact, including African Americans. There are stories yet to be told, whether it's isolated to specific European theater conflicts or outside it. Any competent screenwriter could adapt such stories for the screen. Any competent director could orchestrate their creation for the screen. And yes, people, representing the varied ethnicities that did fight or interacted in some way with the war, could play those parts without fail. And perhaps, just maybe, there is the slight chance that those stories, which screenwriters could develop, that directors could envision and shape, and actors of color could convey on camera--might entertain not only a narrow demographic but general audiences as well.
Hollywood can create just about anything the mind can imagine. Hollywood can create just about anything that can be moderately or hugely successful at the box office. What Hollywood doesn't know is its own potential to use its unbridled imagination to wow every audience it can possibly attracted--and make billions more in the process. Hollywood's first step may not land on the safe, worn path of yesteryear it knows so well but the undiscovered country lying before it still largely unexplored.
